[PATCH v2 1/4] vdpa: add VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK flag

This feature flag allows the driver enabling virtqueues both before and
after DRIVER_OK.

This is needed for software assisted live migration, so userland can
restore the device status in devices with control virtqueue before the
dataplane is enabled.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Shannon Nelson <redacted>
---
 include/uapi/linux/vhost_types.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/uapi/linux/vhost_types.h b/include/uapi/linux/vhost_types.h
index c5690a8992d8..4889e6d70b15 100644
--- a/include/uapi/linux/vhost_types.h
+++ b/include/uapi/linux/vhost_types.h

@@ -165,5 +165,9 @@ struct vhost_vdpa_iova_range {
 #define VHOST_BACKEND_F_SUSPEND  0x4
 /* Device can be resumed */
 #define VHOST_BACKEND_F_RESUME  0x5
+/* Device supports the driver enabling virtqueues both before and after
+ * DRIVER_OK
+ */
+#define VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK  0x6
 
 #endif

-- 
2.31.1